电场极性对甲烷-空气混合气燃烧特性的影响

Effects of the Polarity of Electric Field on Combustion Characteristics of Methane-air Mixture

为进一步研究电场产生离子风的作用机理,本文通过定容弹试验研究了正、负高压电场对甲烷-空气混合气燃烧特性的影响。结果表明:不论电场的极性如何,火焰传播性状均发生明显变化,电场方向上的火焰传播半径和传播速率增加;同时混合气燃烧压力的升高也明显加快。对于不同极性的电场,负电场对混合气燃烧的影响明显强于正电场。施加电压为12kV时,正、负电场作用下混合气的火焰传播速率峰值分别增加了41.7%和62.3%。压力峰值分别增大了8.5%和12.3%,其出现时刻提前了21.1%和31.8%。

In order to further study the mechanism of ionic wind produced by electric field,an experiment on the influences of electric fields with different polarity on the combustion characteristics of methane-air mixture is conducted with a constant volume bomb.The results show that no matter the positive or negative electric field applied,the flame propagation pattern is changed significantly,the propagation radius and propagation rate of flame along the direction of electric field increase,while the combustion pressure rise of mixture also apparently speeds up.For different polarity of electric field,the effects of negative electric field are obviously stronger than that of positive electric field.Under the action of positive and negative electric field with a voltage of 12kV applied,the peaks of flame propagation rate of mixture(A=1.6)increase by 4 1.7%and 6 2.3%respectively,pressure peaks rise by 8.5%and 12.3%respectively and the corresponding timing advance by 21.1%and 31.8%respectively.